Note that the draw triangles functionality includes winding based back faced culling only, this is not the only method of culling to consider, others are;

FRUSTUM CULLING:
A geometry object is usually contained within some kind of bounding area (typically an axis aligned bound box aka aabb or a bounding spere). A frustum is a box defined as the visible area in front of the camera. The aabb or bounding sphere is checked against 6 planes of the frustum to check which side they are on... if they are on the outside, the geometry (and children if you use a scenegraph controlled aka BVH), becomes culled.

OCCLUSION CULLING:
By using hidden planes to define transition ports between game areas, we can occlude areas of the world that are not visible from your current position. There are many ways to do this, portals for example or calculations using spacial subdivisions and what not..

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RipX